People from around the Denver metro area have been sending 9NEWS photos and videos of butterflies for weeks as they flutter around bushes, herbs and flowers.
In fact, butterfly researchers say this is one of the largest migrations they have ever seen across the state!
With snow in the forecast for next week, we wanted to know if that would affect the butterfly migration patterns.
Also, our Facebook community posed several other questions about the butterflies we wanted to help answer.
Meteorologist Cory Reppenhagen headed out to Denver Botanic Gardens and spoke with Rick Levy, a researcher there to answer your questions.
Is there an insane amount of butterflies this year, or are we crazy?
On the 9NEWS Facebook page, Erin Beley asked, "I don't remember seeing this many in years past... is this the first time we've seen this many?"
Answer, from Rick Levy: So, we are not crazy. There are a lot more butterflies of the Painted Lady species this year. They always kind of come through Colorado, but never in this number has it happened like this before. As far as I know, there has never been a migration event like this before.
Is it just Painted Ladies or is it also Monarchs?
Answer, from Rick Levy: It’s just the Painted Ladies. Monarchs don’t typically come through the Front Range as often. In their big migration, we do have some come through, but right now it’s just the Painted Ladies.
How much longer is this going to last?
Answer, from Rick Levy: So, it’s actually quite surprising that it has lasted almost two weeks now. I would say maybe because it’s such a huge boom in their population that it’s lasting so long. Also, you know, people's sunflowers and people's rabbit brush is in full bloom right now, so they are hanging out, getting that nectar that they are enjoying so much. It could last up until the cooler weather next week, and it could even continue on after that, for the ones at least that are still hanging around.
Where are they going, and where are they coming from?
Answer, from Rick Levy: They are coming from the north and heading down to Mexico, but it’s interesting because the ones that leave Mexico are not the ones that are coming back down. So they mate and reproduce constantly throughout their migration.
What is going to happen to them when this winter storm comes on Monday?
On Facebook, Sarah Ann asked us, "Can they hibernate here over the winter and come back in the spring? If so, will they stay or continue their migration?"
Answer, from Rick Levy: The butterflies that are around; a lot of them might actually not make through that because freezing temperatures and insects typically don’t go well together. But, I wouldn’t be surprised if it warms up after that and we still have a few hanging out. But, you know, that’s why they migrate, to escape cold temperatures. They head north as it gets warmer in the spring, and then when it starts to cool down in the fall, that’s when they start heading south.
Can butterflies shelter themselves from cold weather?
Answer, from Rick Levy: Yes, they can shelter. Probably within some thick vegetation or down on the ground, maybe in some small grass, but once you get to freezing temperatures for more than just a short amount of time, that’s when individuals won’t make it out.
Is it sad to see so many butterflies that could die in the storm?
Answer, from Rick Levy: It’s not sad because clearly there was a huge boom in their population, and we have this unprecedented amount of butterflies coming through. A lot of them are making it out. I don’t think it’s sad, I just think it’s how biology works. You have booms and busts, some make it, and some don’t.
So we are just lucky to have seen this?
Answer, from Rick Levy: I think we are extremely lucky to have seen this. I can’t remember being anywhere that had this many butterflies outside, ever.
Is the Painted Butterfly from America?
Another Facebook question came from Nancy Jo, "Is the painted lady invasive or is it a native to Colorado?"
Answer, from Rick Levy: This is actually the most widely distributed species of butterfly in the world. They occur on every continent except Antarctica and Australia. You’ll see these migration events, these butterflies, the same species, is making it out of northern Africa and into Great Britain every year and back.
What is their lifespan?
Answer, from Rick Levy: These adults will lay eggs typically on some sort of thistle, or lots of other plants actually. They are not specialists like Monarchs are, but they’ll lay their eggs and then the caterpillars will hatch, and they will just basically eat. They are like a little eating machine, like a little stomach with a mouth. They’ll do that for maybe a few months, and then they’ll create a cocoon, go in, and come out as an adult butterfly, and they will only live for a few months.
Can you explain why this crazy surge of butterflies is happening this year?
Answer, from Rick Levy: What’s really cool about science is that there’s way more that we don’t know than we do. As far as butterflies and migration, we are only really starting to learn what drives it. Things like weather certainly have a big impact because as you feel that cold weather, they just sort of instinctively know to start moving south.
But it’s just part of their phenology. Phenology is the study of the timing of natural events, when the leaves turn orange in the fall, or when the flowers bloom in the summer. This is also part of that and migration is an important part of that, and what’s also really important is that, not only their timing with the weather, but their timing with their food resources. So, they are coming through the Front Range right now and the rabbit brush are in prime bloom and they’ve got lots of food to be able to eat when they’re coming through.
What can we plant to help attract butterflies?
Several folks on Facebook, including Shaina Klinglesmith, wanted to know, "What can we plant that helps them on their migration?"
Answer, from Rick Levy: It’s good to plant native things in your garden and rabbit brush is one of those things. The butterflies and the bees love it. Rubber rabbit brush is the common name, Ericameria is the genus. I think there’s actually a campaign right now to make it Colorado’s state shrub.
Saturday looks like a really nice day, and maybe the last day to see this butterfly display. Where can we go to see them?
Answer, from Rick Levy: If you really haven’t had time to go out and see them in their full display, go to places that are either big and open and dry. Go to Colorado's lovely plains or anywhere that there is rabbit brush or any type of sunflower in bloom. Also, you can come right here to the Botanic Gardens, there’s probably upwards of 100,000 butterflies hanging out in this garden right now.